Category Archives: All Posts

Background and Setup:

Jason and Nikki Wynn recently proved that, yes, with a specialized setup, you can absolutely have Solar RV Air Conditioning! The definitive proof is here, in their video.

The catch being that The Wynns have a VERY high tech (and therefore VERY expensive!) solar setup on their RV. They’ve gone into tremendous (and extremely helpful!) detail on the cost of parts and installation on their RV in this post on their website. The cost of their solar installation (6 panels, Solar Charge Controller, 700ah of Lithium battery cells, Inverter, AutoGenStart, Battery monitoring kit, Inverter Remote) was a whopping $16,352.74!

Nikki and Jason demonstrated that with their solar installation supplying 85% of it’s listed potential, the Air Conditioner had only about 30-35ah net draw from the battery bank. The question on my mind is this…they have proven that it’s entirely possible on a technical level to run your Air Conditioner off a specialized solar set up……but is it cost effective?

How much does it cost to run a generator?

A quick look around the internet (Gas buddy and other places) reveals that the cost of gasoline has averaged about $2.95 per gallon over the last 10 years. Checking my Onan Generator Manual, I find that the Onan 5500 watt generator will use 0.6 Gallons of Gas per hour when running one Air Conditioner, and will use 1 gallon of gas per hour when running both air conditioners. This means that the cost to run a single Coleman Mach air conditioner using an Onan generator has averaged $1.77 per hour over the last 10 years.

Note that this figure also has implications when it gets warm and you don’t have solar, and you’re deciding between WalMart/Love’s or paying to ‘day-stay’ at an RV park with a power pedestal…even at $4/gallon, boondocking someplace while running the generator to power both Air Conditioners for 10 hours is still more frugal than a $40 RV Park stay.

…but I digress…

How long could The Wynns run Solar RV Air Conditioning?

Jason and Nikki’s battery bank is a 700 amp-hour Lithium LYP Battery bank. They have their charge controller set conservatively to allow them to use 70% of the power from the battery bank (500/700ah used). The LYP battery design, however would allow them to safely discharge the batteries to a 90% drained state (630/700ah used) with no damage.

Jason and Nikki have 960 watts of tiltable solar panels on the roof, and they state in their tech post that this panel setup could supply 54 amps inbound when it’s running at 100%. In the video, it’s supplying 43 amps to their battery bank, meaning it’s running at about 79% peak (idealized) capacity, and the same panel shows that they have ‘banked’ 290 amp hours for the day. Not bad for a sunny day in January!

The Coleman Mach Air Conditioner they have is pulling 76-80 amps when the compressor is running and the unit is cooling, and 27 amps when the compressor is off and only the fan is running. That’s important, because Air Conditioners don’t run their compressors 100% of the time except in the most brutal of conditions. They cycle off and on to keep the coach at a pre-selected temperature, and even when they’re on, the compressor will often cycle on and off to prevent icing in lower temperatures or other specific conditions.

The net draw from the battery bank with the compressor running and the air conditioner cooling the coach is shown in the video to be 36.3 amps.

If we presume that they shot the video around halfway through the day, we can safely presume that they’ll be able to bank another 290 amp hours before sundown, for a daily ‘break even’ total of 580 amp hours stored sunshine for the day.

Daily 580ah solar in divided by 80ah Solar Air Conditioning Draw out means that Nikki could theoretically stand on that kitchen chair for 7h 15m per day with the air conditioning compressor running a 100% duty cycle (always on and cooling), and they would break even on the power stored and used.

If it weren’t particularly hot, and the A/C were only on a 50% duty cycle… Theoretically they could potentially run the air conditioner 14.5 hours per day.

How Does That Compare To Running A Generator?

In extreme (100% duty cycle) heat, running a single Coleman Mach air conditioner 7.25 hours per day means the generator will use 4.35 gallons of gas – at a recent historical average of $2.95 per gallon, the generator will cost $12.93 per day to run.
In moderate heat (50% duty cycle) running a single Coleman Mach air conditioner 14.5 hours per day means the generator will use 8.7 gallons of gas, which will cost, on average, $25.86 per day.

We’ll presume that the average temperature (and duty cycle) for air conditioning will lie somewhere between those two points, and that it would cost $20 per day on average to run the generator to provide AC for the A/C.

How Do The Numbers Shake Out?

Cost of Jason and Nikki’s Solar Installation: $16,352.74
Number of days requiring air conditioning to break even @$20/day: 817.6 days.

At first blush, that seems like a VERY long time, presuming you would ever get to that point without having to replace some expensive parts, like batteries or solar panels.

HOWEVER…

If you were to elect to use your newly found Solar RV Air Conditioning Freedom and decide that you don’t have to chase 70* to keep cool the way you have in the past, and that meant you were to run the air conditioner 180 days per year, a $16,000 solar installation capable of running the coach air conditioning pays for itself in eliminated generator fuel costs in a little over 4.5 years!

Conclusion – YES!

It appears that not only is a specialized solar set-up technically capable of powering a Coleman Mach air conditioner in most climates for the bulk of the year, but it further appears that it is Financially Frugal and NOT Financial Folly to do so!

This seems like a terrific option for people who

Have 60-80 square feet of unshaded roof space.

Have a pile of money that they can spend on a longish return investment.

Would use Air Conditioning at least 180 days per year.

Are exceptionally happy with the RV they currently have, and are unlikely to move coaches.

Note: This entire article relies on some amount of theoretical extrapolation of provided real world values, and that it further hinges on the fact that The Wynns have not yet talked about whether they have stress-tested their Solar Air Conditioning setup to see how many hours of Air Conditioning (at a ‘normal’ thermostat setting of, say, 70*/21*c) they can have before they reach their 70% battery drain cutoff mark on their LYP battery bank. Finally, it relies most heavily on me not having borked up the math someplace. If I did, I’m sure there will be a comment, and I can correct my error(s).

This was where I spent my very first night on the road, January 15, 2015, and I was pleasantly surprised – in fact, this Wal-Mart hasn’t really had any comparison or competition from any Wal-Mart I’ve stayed overnight at since.

I left my apartment in Thornton just as the sun was going down. Packing and making ready had taken MUCH longer than I had anticipated, and involved over 10,000 steps – most of that being more literal than figurative, since the apartment I was emptying was on the second floor. My first stop was the Aurora BestBuy to pick up a Surface Pro 3 so I could work on the road, but that’s a story for another article.

After that, as I was getting back on the road with every intention to make good time toward Amarillo, I spotted the shining feature of this Wal-Mart and had to stop for the night – the dedicated overnight parking for trucks and RVs! That’s right, this Wal-Mart has 11 easy-in, easy out dedicated pull-through spaces for trucks and RVs to overnight in. In addition to the fact that you’re near an enormous Wal-Mart stocked with goods to keep you warm and fed, there are a number of other places nearby that can cater to your needs. There are Verizon, T-Mobile, and Sprint stores, Chipotle with online ordering, Wendy’s, Firehouse Subs, Panda Express, McAlister’s Deli (I highly recommend the carrot cake, and a gallon of tea to go), Chili’s, Starbucks, and Del Taco. Just a little north on Tower Road, there is a BrakesPlus, Discount Tire, and Checker Auto Parts, in case you need a little mechanical help that goes beyond what the Walton Family can provide.

The lot was fairly quiet – there was one refrigerator truck further down the line that ran all night, but I could barely hear it, and traffic died off after most of the stores closed at 9pm.

Overall

4 of 5 Stars – This location is the ideal Wal-Mart for overnight boondocking, but I’m still deducting one star because it’s…overnight boondocking at Wal-Mart.

Directions

From I-70…either direction:

Exit Tower Road headed North
Turn left at the first light – Salida Street
Turn left again your first available opportunity – at the building with Verizon and GNC in it on your left.
Turn left again in the parking lot – you’ll pass the storefronts for Verizon and GNC this time.
The entry is directly ahead of you 300 feet.

Stargazing / Timelapse Opportunities

Every year for the last…one…year, I’ve scored the NFL like it were NASCAR. Wins and Losses don’t count – only points do. Every point counts until you get to the last game of the Regular Season, and then the #1 and #2 ranked teams compare scores, with the team scoring more points in the last game being declared the Cup Winner.
To Recap: In 2015, the Packers (who ended their season with 380 points) took the cup from the Colts (who ended their season with 382 points) when the Packers scored 30 points in the final game of the regular season, to the Colts 27 points.

The NFL Season got started without me this year, and I just now realized it’s That Time Again. Here are the cumulative results for Week 4 of NFL-NASCAR!

As much as I hate to do this, I’m definitely going to have to give the Raiders the nod for Most Improved Team. This week last year, they had scored a paltry 51 points compared to this year’s 97 points, and after just 4 games in the 2016 season, they’ve already scored more than half of their entire 2015 Point Total.

For the last several nights, I’ve wanted to go outside and experiment some more with the GoPro Night Lapse mode to capture satellite trails, since I had so much fun watching them in Folsom when I was camping with RV Lady. However, night after night, it’s been too late when I look up the passes for the evening on Heaven’s Above, all the bright passes had already ended for the evening. I think it has something to do with being this far south, but it’s pretty rare to have a visible satellite pass after about 9:30pm, and they start shortly after 7pm. In Folsom the last passes were much closer to 10:30, and they’d start about 8:15.

Well, tonight I remembered in the nick of time to check Heaven’s Above, and I saw that the ISS was passing overhead, and for once, it wasn’t a “barely visible down on the horizon” pass, but up at a respectable 40+ degrees! The down side is that I only had about 5 minutes to prepare!

BEHOLD THE FIVE MINUTE PREP-TIME ISS PASS!

The top to bottom trail, and the two at the bottom right are aircraft. The horizontal pass with small gaps is the ISS. This is a series of 12 images shot with a Hero 4 Silver in GoPro Night Lapse mode with ProTune turned on. 15 second exposures on Continuous mode, with an ISO limit of 200, GoPro color turned on and composited in Markus Enzweiler’s excellent StarStax.

CAT FOOD BASICS:
Cats are obligate carnivores, which means they require nutrients that are found ONLY in animal tissue. Cats need tons of protein and have no need for carbohydrates in their diets. Carbs basically just make cats fat and cause diseases, but dry cat foods are loaded with carbs because they help the kibble stick together in the manufacturing process. Canned foods are all very low in carbohydrates. Canned foods also have the added benefit of forcing your cat to consume more water, which is great because many of the most common cat diseases are improved by increasing water intake (kidney disease, UTIs, blockages, crystals, etc.).

So here are the criteria for a good cat food:

High Protein

Low in Carbohydrates

High in Moisture

High-Quality Ingredients

If we’re looking at just carbohydrates and protein, canned food is better than dry food. Even the cheapest grocery store generic canned food is better than 99% of dry foods. Canned food is more expensive and less convenient, so to keep things simple, there are separate lists for canned foods and dry foods. The brands are primarily ranked on nutrient makeup (carbs & protein), and then bumped down a notch or two for containing low-quality ingredients.

For brands in this list, if one company makes grain-free and non-grain-free foods, you can usually assume that their grain-free food is at least marginally better (lower carbs, higher protein). You can also assume that any formula labeled “light, diet, weight control, or indoor” is at least marginally worse (higher carbs) than the regular stuff from the same brand.

Some flavors of food are significantly better than other flavors of the same brand. There is a huge amount of variation. If you want more detailed and accurate information, post in this thread and we’d be happy to help you choose.

CAT FOOD BRANDS

Premium Canned Foods — These foods are very low in carbohydrates and very high in protein. They also use excellent ingredients (no corn, soy, byproducts, or anything like that). Generally <15% of the calories in these foods come from carbohydrates, which is what your cat is designed to eat.

Good Canned Foods — These foods are mostly a little higher in carbs and a little lower in protein, or they use some lower-quality ingredients in relatively small amounts. But they’re still very good foods and better than most dry foods.

Acceptable Canned Foods — These foods are mostly still better than dry foods in terms of nutrients, but many of them use byproducts, corn, and soy as protein sources. They may also use artifical presevatives/colors, menadione, and other low-quality ingredients. How good these foods are varies A LOT from flavor to flavor. If you have to feed these foods, I recommend that you 1) look at these two charts (here and here) and choose flavors with the biggest numbers in the protein column and the smallest numbers in the carb column, and 2) read the ingredient labels and pick the flavors with the least awful ingredients. You should also know that most of these “cheaper” canned foods contain significantly more water than the premium foods, which means you may not be saving as much money as you think. For example, if you compare the cost based on calories (instead of ounces), many Fancy Feast flavors are more expensive than Wellness.

Next, Dry Foods. In case you missed this before, CANNED FOOD IS BETTER THAN DRY FOOD FOR CATS.

Good Dry Foods — These are the few dry foods that are almost as good as canned food (in terms of being low in carbs and high in protein). If it weren’t for the fact that they lack moisture, these would be equivalent to Premium or Good canned foods. These foods are also extremely dense in terms of calories per cup of food, so many cats will eat 1/3-1/2 cups a day or less. In short, you’re getting more bang for your buck.
(For example, if you compare the costs based on calories (instead of lbs or kgs), Solid Gold Indigo Moon is cheaper than A LOT of dry foods, including Purina, lots of grocery store crap, and almost every food on the Acceptable list. These foods are expensive by the pound, but they really only cost $6-12 per month to feed an average sized cat.)

Acceptable Dry Foods— These foods use good ingredients, but they’re too high in carbohydrates and/or too low in protein. Nutritionally, they’re not as good as almost any canned food, but you could do a LOT worse. (These are mostly in the range of 25-30% carbohydrates; there are almost no canned foods this high in carbohydrates.)

Poor Dry Foods — These aren’t quite as bad as the Awful Dry Foods, but they’re close. These foods either have decent ingredients but huge amounts of carbohydrates, OR they have awful ingredients and moderate amounts of carbohydrates . Most of these are also pretty overpriced for what you’re getting.

Awful Dry Foods — These foods are the worst – awful ingredients and tons of carbs. They’re loaded with corn, soy, and byproducts. Many of these contain the minimum amount of protein required to be legally labeled “cat food”. Many contain more carbohydrates than protein, which is a recipe for greasy, obese, diabetic cats.